3,901 reputation
916
bio website
location London, United Kingdom
age 43
visits member for 5 years, 2 months
seen Aug 5 at 11:13
Quite boring, really. Have faffed about with computers since the mid-80s, have worked as a network engineer, unix sysadmin and (occasionally) developer.

Aug
5
answered Routing VoIP and Internet traffic
Aug
5
comment Is it normal to have a private range IP in a traceroute?
@womble: If you go for private IPs on you backbone links (something that used to be recommended, to preserve IPv4 space), you will want to leak a small subset of control packets from them (TTL exceeded, Fragmentation needed, possibly a few more).
Aug
2
answered Understanding Ports: How do multiple browser tabs communicate at the same time?
Aug
1
comment cisco router : redirect any dns request to my own dns server
@qwildz: It probably varies from router to router, but enabling policy-routing tends to drop from CEF to slower forwarding algorithms. On low-end hardware, it tends to end up being CPU-switched.
Jul
31
comment Certificate Authority impersonation
@Zoredache: Typically, in a public-key cryptosystem, you have, for a message M and a key-pair P,S and two operation E,D that D(P,E(S,M)) == D(S, E(P, M)) == M; that is, encryption of a plain-text with one half of the key-pair, followed by decryption of the crypto-text with the other half of the key-pair results in the plain-text.
Jul
31
answered cisco router : redirect any dns request to my own dns server
Jul
27
comment IPv4 address to Netmask mapping and Multiple default routes feasibility?
I think Linux will, by default, do round-robin load-balancing between default gateways with the same metric. In some situations, this is exactly what you want, in others it will break things horribly. Keeping to a single default gateway or having different metrics is definitely the safe bet.
Jul
26
comment Small office network labeling
Labeling each end of the cable with both pieces of kit it plugs into is a good idea, as long as you relabel the cable as soon as anything changes...
Jul
25
answered Our security auditor is an idiot. How do I give him the information he wants?
Jul
24
answered What are some great network diagram techniques?
Jul
15
comment web page slow load due to long DNS lookup
How frequently do you need to change them? How long is it acceptable that a DNS lookup points to an old IP address after a change? How long in advance do you know that you will need to make a change? Once you have the answers to those questions, picking a number of seconds for the (default) TTL should be not-too-hard. I've seen TTLs in the region of 3600-86400 work fairly well (that allows a client to cache the lookup for 1h-1d) and if you know you have a change coming up, you can always push the TTL down to 600-or-so 1.5 (default) TTLs before you do the change.
Jul
12
answered LAN Traffic Monitoring Tool
Jul
11
answered Finding IP of Network Switch
Jul
8
awarded  Synonymizer
Jul
1
answered Steps to take when technical staff leave
Jul
1
comment Cisco ACL Not Applying
You can certainly apply a single ACL both in- and out-bound. I have done it multiple times. Admittedly prima=rily for "tracking" ACLs (with specific "ip permit" statements for what I am interested in, finishing with a blanket "ip permit any any")
Jun
20
revised bad network adapter takes down entire network?
added 1 characters in body
Jun
17
comment Isolating one router port from the rest
By default, the router will happily route traffic between A,B on one side and C on the other. However, broadcast traffic will not pass between the two VLANs.
Jun
17
answered Isolating one router port from the rest
Jun
17
answered bad network adapter takes down entire network?